Quick Navigation

Paleolithic Diet

Paleo diets are a set of eating patterns that limit or exclude foods that were unavailable to our Paleolithic ancestors. Randomized trials suggest well-formulated paleo diets may be as effective as other healthy diets for weight loss and improving markers of metabolic health. Risks of a well-formulated paleo diet are minimal, but more restrictive versions can cause nutrient deficiencies and health issues.

Our evidence-based analysis on paleolithic diet features 84 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
Last Updated:

Easily stay on top of the latest nutrition research

Become an Examine Member to get access to all of the latest nutrition research:

  • Unlock information on 400+ supplements and 600+ health topics.
  • Get a monthly report summarizing studies in the health categories that matter specifically to you.
  • Access detailed breakdowns of the most important scientific studies.

Try FREE for 14 days

Research Breakdown on Paleolithic Diet


1What is a paleo diet?

“Paleo” — short for Paleolithic, denoting a time period roughly 2.5 million to around 10,000 years ago [21][22] — refers to a diet and lifestyle that aims to reproduce that of preagricultural humans and their ancestors. The premise of paleo diets is that modern diseases have arisen from the mismatch between the environment in which humans evolved and that of modern society (aka the evolutionary discordance hypothesis).[1][23]

Paleo diets vary in their restrictiveness, but most include fruits, vegetables, nuts, meat, and eggs. Some versions exclude grains, legumes, dairy products, and nightshades (e.g., tomatoes and eggplant), and all versions restrict sugar and refined grains, among other processed foods.[1] 

Characteristics of different paleo diets
Type of paleo dietEmphasizeLimitEliminate

Paleo diet used in research studies[1]

  • Fruits

  • Nuts

  • Vegetables

  • Fish

  • Eggs

  • Meat

  • Dairy

  • Grains

  • Legumes

  • Ultraprocessed foods

  • Processed culinary ingredients

  • Alcohol✝

Meat-heavy fad paleo diets (i.e., “The Stone Age Diet”)

  • Meat

  • Fish

  • Eggs

  • Fruits

  • Nuts

  • Vegetables (esp. starchy root vegs)

  • Dairy✝

  • Grains

  • Legumes✝

  • Ultraprocessed foods

  • Processed culinary ingredients

  • Alcohol

What paleolithic ancestors probably ate [24][25][26]

  • Fruits

  • Nuts

  • Vegetables

  • Grains

  • Legumes

  • Fish

  • Eggs

  • (Lean) Meat

(amount of each depends on local availability)

Undetermined

  • Ultraprocessed foods (e.g., refined grains, sugar)

  • Dairy

  • Alcohol

Disagreement on whether a food should be eliminated or not is indicated with a “ ✝ “.

1.1What are other names for the paleo diet?

The paleolithic diet goes by many other names, including paleo diet, ancestral diet, primal diet, hunter-gatherer diet, evolutionarily appropriate diet, caveman diet, Stone Age diet, evolutionary eating, and, simply, paleo.

Some of these (e.g., the Stone Age diet, primal diet, and original The Paleo Diet™) offer different dietary recommendations but resemble each other enough to be categorized as paleo diets.

1.2What are other versions of the paleo diet?

Related diets include the Paleo Autoimmune Protocol and the Wahls Protocol.

The Paleo Autoimmune Protocol is a two-stage elimination diet. First, foods typically excluded on a paleo diet are removed. Then, after a period, the eliminated foods are added back one by one to see if they cause negative symptoms.[27][28][29]

The Wahls Protocol is another restrictive diet that aims to address autoimmunity issues and is sometimes referred to as a modified paleo diet.[30]

Carnivore diets and raw-food diets share some philosophical principles with the modern paleo lifestyle — namely, their premise on the evolutionary discordance hypothesis. Carnivore diets are completely (or almost completely) animal-based diets. Raw-food diets range from vegan to carnivore, but no processing or heat treatment is permitted. When these diets are more paleo than not, they are often labeled “carnivore paleo” or “raw paleo” in colloquial usage. These diets have not been studied in interventional trials.

Low-carbohydrate paleo diets can cause nutritional ketosis; some paleo diets are ketogenic, and some keto diets are paleo.

Timeline of important dietary developments in (pre-)human history
Cultural periodsApproximate datesImportant dietary developments

Paleolithic period*

2.5 million ya to 10,000 – 12,000 ya[21][22]

  • 2.5–2.6 million ya - first use of stone tools for processing meat [21]

  • 30–250 kya - earliest fire and hearth structures [21]

  • 100–130 kya - earliest evidence of seed and wheat-predecessor consumption[24]

  • 44–100 kya - possible first evidence of bean consumption[24]

  • 30 kya - early evidence of starchy root vegetable processing [31]

Mesolithic period

10,000 – 12,000 ya to 8,000 – 5,500 ya[32][33]

  • 2.5–2.6 million ya - first use of stone tools for processing meat [21]

  • 30–250 kya - earliest fire and hearth structures [21]

  • 100–130 kya - earliest evidence of seed and wheat-predecessor consumption[24]

  • 44–100 kya - possible first evidence of bean consumption[24]

  • 30 kya - early evidence of starchy root vegetable processing [31]

Neolithic period

8,000 – 5,500 ya to the beginning of the Bronze Age (depending on location)[22]

  • Widespread agrarian practices (e.g., domestication of plants and animals, food production practices) mark the beginning of the Neolithic period

ya = years ago kya = thousand years ago

*Anatomically modern humans first appeared around 200 kya and dispersed out of Africa around 50 ka. Many of the dietary developments in the Paleolithic Period occurred among pre-human ancestors or evolutionary cousins, not modern humans.

2🔍 Digging Deeper: When was the Stone Age?

The Stone Age refers to a cultural period from 2.5 – 2.6 million to about 8,000 – 5,500 years ago (depending on the region). This age is characterized by archaeological evidence of stone tool use, and is classified into three periods: Paleolithic, Mesolithic, and Neolithic, referring to Old, Middle, and New Stone Age.

The paleolithic period, starting about 2.6 million years ago, included pre-human ancestors and was the stage for the emergence of anatomically modern homo sapiens.

Following the Paleolithic period is the Mesolithic period, starting about 10,000–12,000 years ago and ending around 6,000 years ago. The cultural and technological transition to a more agrarian lifestyle characterize this period.

The Neolithic period, which started about 6,000 years ago and ended 2,000 – 3,000 years ago with the development of the Bronze Age in some regions, describes the final anthropological age in which stone tools predominated.[32][33] Each of these cutoffs is defined by the anthropological evidence of particular regions and may vary by thousands of years, depending on geographical area. [22][34][35][22]

3How does paleo compare with other diets?

Compared with standard Western diets and healthy eating guidelines, paleo diets include more calories from protein and fat and fewer from carbohydrates, according to the dietary intake data in interventional studies.

Compared with some Westerners’ baseline diets, paleo diets generally provide more polyunsaturated (i.e., omega-3s) and monounsaturated fatty acids and carotenoids, as well as potentially more fiber and potassium, while providing less sodium, less saturated fat, and less sugar.[30][13][8]

Compared with national healthy eating guidelines, however, paleo diets have been shown to be lower in calcium and iodine.[13][12] Theoretically, they may also provide less potassium and fiber and more saturated fat than healthy diet guidelines.[15]

4Are paleo diets healthy?

A moderate, sensible, nonrestrictive paleo diet that generally fits within the contemporary, evidence-based ideas of paleo nutrition is likely to be healthy. A highly restrictive, unsustainable paleo diet, on the other hand, can lead to adverse health outcomes.

More studies have been conducted on paleo diets for their effects on weight and markers of cardiometabolic health than on any other outcome. Averaged across studies, paleo diets appear to have a positive effect on these outcomes, comparable to other healthy diets.[3][2] Conclusions on long-term outcomes are impossible to make, but one epidemiological study that watched people’s disease rates over time suggests that people with a diet closer to paleo may have a lower risk of death from all causes, compared with people whose diet is furthest from paleo.[36] 

Paleo diets typically include more animal protein and fewer grains, dairy products, and legumes than recommended by official organizations, which could contribute to ill health. On the other hand, paleo diets also encourage lean meats, fruits, and vegetables and restrict alcohol, refined grains, added sugars, and ultraprocessed foods, which jibes with many of the requirements for healthy diets outlined by the FDA, American Institute for Cancer Research, and American Cancer Society.[37]

Paleo diets are sometimes misconstrued as being high in saturated fat. Although that’s certainly a possibility, the results of rigorous studies suggest that paleo diets generally lead to a decrease in saturated fat and increase in unsaturated fat intake.[30][13][8] 

Overall, the diet that works is the one you can stick to, and some studies suggest that people have a hard time sticking to paleo, with only 3 out of 4 participants able to adhere to it for 2 years.[8][38] Restrictive paleo diets, such as the paleo autoimmune protocol and popularized fad versions, entail even greater dietary restriction, which increases the risk and difficulty. Adopting a more restrictive paleo diet should be supervised by a qualified healthcare professional to ensure the diet is supportive of — not damaging to — your health.

5What are the benefits of a paleo diet?

Most interventional studies comparing a moderate paleo diet to a typical Western diet show marked health improvements with a paleo diet, whereas comparison to one of any number of national healthy eating guidelines reveals comparable positive effects among the groups studied.[3]

A modest body of research shows that a typical paleo diet may help people lose weight and may promote health, including studies showing positive outcomes for body composition;[4][3] markers of metabolic syndrome,[7] markers of diabetes and insulin resistance;[5][6] blood lipid markers of heart disease;[7][4] and observational data for oxidative stress[39] and cancer.[36][40] The scant evidence available for autoimmune conditions suggests minor, potentially irrelevant, improvements for multiple sclerosis[41][42] and inflammatory bowel diseases.[27] The evidence suggests a consistent, if not always significant, decrease in blood pressure across studies.[7][4]

6Is paleo good for weight loss?

Paleo diets can lead to greater weight loss than other healthy diets in the short term, but after 6 months, their effect on weight is comparable to other healthy diets.

The longest paleo diet study (2 years) shows that it can lead to greater weight loss over 6 months compared with other healthy diets, but this beneficial effect may not extend to a year or longer, which may be due to an adaptation effect or issues with long-term adherence.[8][3] (Additionally, for low-carb paleo diets, part of the initial weight loss may be due to glycogen depletion. Several meta-analyses have found that paleo diets reduce weight by 1.4–3.9 kg (3.1 –8.5 pounds), reduce BMI by 1.1–1.7 kg/m2, and decrease waist circumference by 2.5–3.1 centimeters (1–1.25 inches) more than control diets.[2][3][4]

Trials using the gold standard for fat mass measurements, dual-energy X-ray absorptiometry (DXA),[8] showed no difference in fat loss between participants who ate a paleo diet versus another healthy diet.[43] Trials that used the less reliable method of bioelectrical impedance analysis (measured using the rate at which an electrical current runs through the body) found that a paleo diet reduced fat mass more than a control diet did.[13][44] 

Paleo diets lead to weight loss because people tend to eat fewer total calories, even though most studies tell participants to not intentionally restrict calories. Eating a paleo diet may result in consuming 108–451 fewer kilocalories daily than on a control diet. [43][8][13] 

The effect on reducing calorie intake may be attributed to the high quantities of protein, fats, and fiber in most paleo diets, which contribute to a high level of satiety (feeling full). Compared with healthy eating guidelines, paleo meals lead to a relative increase in the satiety hormones glucagon-like peptide-1 (GLP-1) and peptide YY, [16] or a decrease in the fat hormone leptin,[17] but probably not due to ghrelin, the hunger hormone.[45] On the flip side, other diets (e.g., low-fat or high-unsaturated-fat diets) are associated with greater before-meal hunger compared with a paleo diet.[45] Over the long run, this satiating effect may translate to reduced calorie intake, greater weight loss, and a reduction in the risk of related cardiometabolic diseases.[46]

7Is paleo good for people with type 2 diabetes?

Paleo appears to be effective for managing markers of diabetes, at least in the short term and to a similar extent as diets based on other healthy eating guidelines that also lead to weight loss.

In people with diabetes, paleo diets have a greater effect on reducing insulin resistance (using the homeostatic model assessment for insulin resistance, or HOMA-IR) and blood insulin compared with other healthy diets.[5] Among people with, or at high risk of, diabetes, paleo appears to have a similar, but not superior, effect on lowering elevated hemoglobin A1c (HbA1c, an average blood sugar measurement over 3 months), glucose, and HOMA-IR as other healthy diets.[5][6]

Paleo diets have a small effect on levels of the inflammation marker C-reactive protein (CRP) among people with type 2 diabetes[47] and people at high cardiometabolic risk. [4][5]

The positive effects of weight loss on blood sugar and insulin regulation are well established, regardless of the diet used to achieve it.[48][49] Since people on a paleo diet tend to lose weight, the diet also tends to show favorable effects on markers of type 2 diabetes.[2][3][4] The low-glycemic sources of carbohydrates[20] and lower total carbohydrate content[19] in paleo diets may also play a role in glycemic regulation, but whether the diet’s beneficial effect is due to its specific composition or its effect on weight loss has not been directly studied.

8Is paleo good for blood pressure, cholesterol, and other heart health markers?

Overall, paleo seems to have small, mostly positive effects on markers of cardiometabolic health, including weight, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. Positive effects on blood pressure are seen less consistently across studies.

Paleo may lead to a consistent (but not always significant) decrease in blood pressure across short-term studies when compared with other healthy diets.[7][4] The variable effect of paleo on blood pressure may be due to the different makeup of individual paleo diets. Eating less sodium and more potassium lowers blood pressure;[50] more magnesium and a higher ratio of unsaturated fat to saturated fat may also contribute.[5] 

When it comes to blood lipids, randomized studies suggest that a paleo diet decreases triglycerides and LDL-C,[3][7][4][5] though one nonrandomized, noncontrolled trial showed that an unrestricted paleo diet can raise LDL-C.[51] The positive effect on HDL-C is less clear.[7] 

The effect on lowering triglycerides is likely due to eating less total refined carbohydrates, in particular, sugar.[18] A decrease in LDL-C and increase in HDL-C[4][7] may be attributed to paleo’s high omega-3 fatty acid content and favorable ratio of unsaturated to saturated fats.[13][8] On the other hand, LDL-C may rise when dietary saturated fat is eaten in place of carbohydrates or unsaturated fats.[52][53] This relationship might not hold true for paleo diets that are also ketogenic.[54][55]

9Does the paleo diet affect cancer?

No interventional trials have looked at the relationship between a paleo diet and cancer development, progression, or recurrence. In one retrospective case-control study, people without endoscopy-confirmed colorectal cancer were marginally more likely to eat a diet that adhered to general paleo principles compared with people who followed a diet least similar to paleo.[40] A more rigorous prospective observational study showed that participants who ate a diet most similar to paleo were less likely to die of cancer than those who followed a diet most removed from paleo.[36]

10Is paleo good for inflammatory autoimmune conditions?

Two elimination diets modeled on paleo have been studied in small trials for their effects on inflammatory bowel diseases and multiple sclerosis, but not on other autoimmune diseases. The results suggested by these underpowered studies need to be confirmed by larger trials, but paleo diets may positively affect subjective outcomes like quality of life and level of fatigue to a small extent.

10.1Paleo Autoimmune Protocol and inflammatory bowel diseases

The Paleo Autoimmune Protocol (AIP) is an elimination diet based on paleo and developed by biologist researcher Sarah Ballantyne, PhD. The one before-and-after study on people with Crohn’s disease or ulcerative colitis used the “SAD to AIP in Six” — SAD standing for the standard American diet — diet transition program, in which participants went through an elimination phase followed by a highly restricted maintenance phase.[27] Negative symptoms decreased, and 73% of participants achieved and maintained clinical remission during the study. The downward trend in fecal calprotectin (a marker of inflammation in inflammatory bowel disease) was not significant, and researchers observed no effect on CRP or any other biomarker.[27] 

10.2Paleo AIP and Hashimoto’s thyroiditis

Only a single before-and-after study has been conducted on the paleo AIP’s effect on Hashimoto’s thyroiditis.[28] Compared to baseline, mild improvements in quality of life were reported.

10.3Wahls Protocol and multiple sclerosis

Another paleo-based dietary protocol, developed by Terry Wahls, MD, has been studied for its effect on multiple sclerosis with and without a lifestyle component. Each randomized study showed a modest improvement in quality of life and level of fatigue but no change in disease activity when compared to a typical American diet,[41] MCT oil-based ketogenic diet,[56] or low-fat diet.[42]

11What is the history of the paleo diet?

For almost a century, diets informed by evolutionary biology and paleoanthropology have enjoyed a presence in popular media. Weston A. Price’s “Nutrition and Physical Degeneration: A Comparison of Primitive and Modern Diets and Their Effects” in 1937 is one early example, but only since Walter Voegtlin’s 1975 chiefly carnivorous “The Stone Age Diet” have these ancestral diet theories come together to form the popular “paleolithic diet” recognized today.[26][57] 

The next wave of paleo diet science came in 1985. S. Boyd Eaton, MD, and Melvin Konner, MD, analyzed data from George Murdock’s 1967 “Ethnographic Atlas” and suggested that typical paleolithic diets completely excluded dairy, potentially included tiny amounts of grains, and often included roots, beans, nuts, tubers, and fruits. Eaton and Konner estimated that in the average paleolithic diet, 33% of calories came from protein, 21% from fat, and 44% from carbohydrates, but they noted that variation in macronutrient composition was the rule.[23]. From these investigations, Eaton published “Paleolithic Prescription” to reach popular audiences in 1988. By 1997, the authors had expanded their data set and showed that a model of the diets of small, traditional societies were more nutrient dense than modern diets.[58]

In 2002 the paleo diet’s eponymous book by Loren Cordain, PhD, ushered in a new level of popular interest in evolutionary eating. Going off the (mistaken[59][60][61][25][24]) perspective that human digestion and genetics have remained unchanged for more than 10,000 years, and the then-current paleoanthropological research which suggested that animal foods made up the majority of Paleolithic diets,[62] Cordain’s paleo is heavy on meat and excludes all grains, dairy, and legumes.

In subsequent years, paleo protocols have multiplied, resulting in a dizzying variety of paleo diets. Emerging from this trend, the paleo-esque AIP and Wahls Protocol are evidence-based, medically supervised elimination diets that restrict foods commonly discouraged by paleo diets.[30][27]

As proponents of paleo update their evidence base, contemporary paleo diets are becoming more flexible and more able to suit individual needs. “Paleo”-branded products proliferate, blurring the line between what is and is not paleo. The history of the paleo movement shows that if there is one thing we know about paleo, it’s that the paleo diet doesn’t exist: there was no single diet of our Paleolithic ancestors, and there is no single paleo diet today.

12What did Paleolithic humans actually eat?

The diverse dietary patterns of hunter-gatherers were largely determined by geography. Notwithstanding the claims made by popular paleo diet doctrines, grains (including wheat), tubers, roots, and legumes were all consumed by our Paleolithic ancestors. In addition, nuts, seeds, animal products, honey, and other plants were all regular features of a Paleolithic-era diet, and milk consumption emerged in the Mesolithic and Paleolithic periods.

Contemporary evidence reveals that early notions of the Paleolithic diet were inadequately informed and excessively restrictive.[26] Insights from dietary paleoanthropology show that diversity is the rule when it comes to defining the diet of hunter-gatherers. Geography and climate strongly correlate to the sources of calories in ancestral peoples’ diets. The proportion of calories from plant sources versus animal sources is correlated to geographic latitude, with equatorial populations consuming more calories from plants.[26] 

Evidence of grain and legume consumption has been documented in Paleolithic archaeological sites.[24] Dairy was widely consumed around 6,000 years ago, and human genetics have changed since then to accommodate the digestion of lactose.[63][60][61] Some foods available today provide fewer nutrients than those available only 70 years ago, calling into question whether it is even possible to eat like a Paleolithic human.[64]

The development of lactase persistence — the continued activity of the lactase enzyme in adulthood — which allows adults to consume lactose in dairy with no digestive ill effects, has been documented as an evolutionary adaptation in some populations starting about 5,000–10,000 years ago by at least two research groups.[60][61] Even if this evidence supports the idea that dairy is a Mesolithic or Neolithic addition to the human diet, it refutes the principle that human genetics have not changed since the Paleolithic age. Whereas evidence suggests digestion-related genes have changed as recently as 5000 years ago among some humans, the Paleolithic period ended about 8,000–12,000 years ago among those populations who developed lactase persistence.[34][35]

The emphasis on meat in early conceptions of paleo was supported by the scientific literature available then (i.e., Murdock's “Ethnographic Atlas”). However, an absence of evidence, rather than evidence of absence, may have led to the unwarranted exclusion of plant foods. More systematic, recent investigations on the teeth, fecal remains, and stone tools of early humans suggest that almost all small-scale Paleolithic societies gathered, processed, cooked, and consumed a variety of grains, including grass-seed predecessors to modern wheat and other grains, as well as other seeds, roots, and beans.[25][31][24]

Together, this research suggests that rather than one paleo diet, the diets of Paleolithic humans differed by location and culture and included a variety of foods. Additionally, evidence for recent evolutionary adaptations to Neolithic foods casts doubt on the belief held by many paleo doctrines that genetics are rigid.

13How safe is a paleo diet?

13.1Are there any major side effects or adverse events with paleo diets?

Paleo diets are safe for most people. Reports of adverse events are rare in research studies, but they’re not always monitored, which may reflect a lack of evidence. Most adverse events are found in one-off case reports of people using a highly restrictive version of the diet, which limits the ability to apply these observations to other settings.

One trial that rigorously followed adverse events found little evidence of negative effects with a moderate paleo diet. [65] However, when implementing a more restrictive paleo AIP diet, one study participant with a preexisting bowel stricture dropped out due to a bowel obstruction caused by the diet. [27]

Case studies have drawn a connection between ketoacidosis (a harmful level of acid in the blood) and calorie- or carbohydrate-restricted paleo diets among lactating women.[9] Additionally, excessive urination (polyuria) was linked to a low-carbohydrate paleo diet in a 2-year-old boy.[66] In another case study, a low-carb paleo diet was connected to a red rash called prurigo pigmentosa in a middle-aged woman who had lost significant weight.[67] In all cases, adverse symptoms resolved when the affected individual reintroduced carbohydrates to their diet, suggesting that the level of carbohydrate restriction, not the paleo diet itself, was the cause.

When implemented improperly (e.g., without adequate seafood, iodized salt, or dairy), paleo can lower iodine intake,[13][12] which may impair thyroid function. Additionally, low calcium intake on a paleo diet may be problematic for bone health.[13][14]

13.2Are there long-term risks with a paleo diet?

Long-term consequences of a paleo diet have not been studied. The longest randomized trial is 24 months[8] and did not show an increase in side effects in the long term.

Some observational studies found a link between an increased risk of cardiovascular disease, cancer, and kidney disease and a higher intake of red meat.[68] High-protein diets may be associated with risk of kidney problems as well, but this association has been inconsistent.[69] Low-carbohydrate diets are independently associated with an increased risk of adverse effects such as kidney stones, elevated LDL-C, and (rarely) ketoacidosis.[70]

13.3Is paleo safe for your kidneys?

Moderate paleo diets appear to be safe for healthy kidneys, but paleo diets that are very high in protein may impair kidney function, and ketogenic paleo diets that are very low in carbs may increase risk for kidney stones. These risks are elevated in people whose kidney function is already impaired.

Unfortunately, no randomized clinical trials have tested the effect of a paleo diet on renal function. People with renal disease are sometimes excluded from paleo clinical trials, which limits the conclusions we can draw from the research literature. Additionally, no kidney-related adverse events have been reported in paleo diet clinical trials.

The effect a paleo diet has on your kidneys must be interpreted from research on similar dietary patterns, such as high-protein or low-carb diets, which have been studied for their effects on renal function.

In one before-and-after study, participants at a stable weight on a low-carb, high-protein diet (33% of calories from protein) had a high renal acid load, which increased their risk factors for kidney stone formation.[10]

Epidemiological evidence shows an inconsistent link between diets higher in animal protein and risk for kidney stones and renal impairment.[71][69][72] Among people with type 2 diabetes, a paleo diet produced lower estimated net acid excretion, which is associated with a higher risk of kidney disease progression,[73] than an American Diabetes Association diet.[74] On the other hand, estimated net acid excretion may not accurately represent true net acid excretion in the context of a diet high in protein, fruit, and vegetables, since some fruits may counteract the metabolic effects of animal protein.[74]

Moderate protein diets — around 0.8 g/kg of body weight — have been shown to be safe among people at risk for kidney disease,[75] and protein intake as high as 1.1 g/kg may be safe for people with diabetes-induced kidney damage.[76] Among people who have a stable weight, diets that include 10–20% of calories from protein for people below age 65 or 15–20% for people above age 65 are safe. Higher-protein weight-loss diets, in which 20–30% of calories come from protein, may have a net-positive effect among people with metabolic dysregulation (e.g., overweight, type 2 diabetes) considering how important protein is for successful calorie restriction.[75] Eating more plant-based proteins, which may be excluded in some popular paleo diets, is associated with lower risk of kidney damage than eating more protein from animal sources.[77] Conversely, diets high in animal protein may be linked to an increased risk of kidney damage compared with diets low in animal protein.[78]

For healthy individuals, the risk of moderate-to-high protein consumption on kidney function appears to be insignificant in the context of an otherwise healthy diet (i.e., a moderate diet low in sugar and salt). In studies mostly 6 months or shorter on healthy individuals, protein intake on the higher side but still within the recommended range (1.8–2.5 grams of protein/kg/day) was associated with elevated glomular filtration rate within the range of normal kidney function.[11]

13.4Is paleo safe for children and pregnant or nursing women?

Though generally considered safe, extreme paleo diets may pose risks for children and pregnant women.

Low-carbohydrate, low-calorie paleo diets have been connected with lactation ketoacidosis in multiple case studies.[9][79] This rare condition may arise when a lactating woman’s calorie needs are not being met through diet.[80] Whether acidosis was caused chiefly by calorie restriction, carbohydrate restriction, an element of the paleo diet itself, or the patients’ own metabolic or genetic abnormalities is unknown, but these case studies showed that the condition always resolved with the reintroduction of dietary carbohydrates.

One other case report connected a low-carbohydrate paleo diet with excessive urination in a 2-year-old boy.[66] Ketogenic diets, which sometimes include paleo, may delay growth in children.[70]

13.5Does the paleo diet lead to any nutrient deficiencies?

A well-formulated paleo diet is unlikely to lead to any stark nutrient deficiencies. When they do occur, the nutrients most likely to be insufficient are iodine, calcium, and vitamin D.

Iodine is one of the more likely insufficiencies because much of itin Western diets comes from fortified foods like iodized salt and iodine used in producing cow’s milk.[81] 

Evidence from clinical trials shows that iodine intake may be lower,[13] and the rate of iodine deficiency higher (from a prevalence of 15% to 73% over 6 months), [12] among people on a paleo diet compared with people adhering to healthy eating guidelines. Paleo-friendly iodine sources include seafood, particularly seaweed, cod, and oysters.

Calcium, typically from dairy products, is another potential nutrient insufficiency on a paleo diet.[13][14] The best paleo source of calcium is bone-in canned fish, which may not be permitted in more strict versions that disallow all processed foods. Otherwise, some leafy greens of the cabbage family and bonemeal are good sources of calcium on paleo.

Vitamin D, a nutrient in which people are commonly deficient regardless of diet,[82] may theoretically be hard to come by in a paleo diet.[15] On the other hand, vitamin D deficiency in connection with a paleo diet has not been reported in scientific literature. This may be because it has not been measured, either because fish-forward paleo diets provide sufficient vitamin D or because appropriate sun exposure — from which the body generates vitamin D — is a component of some paleo lifestyle recommendations.

13.6Should you take supplements on a paleo diet?

Since iodine, calcium, vitamin D, and other essential nutrients may be low in a paleo diet, talk to your healthcare provider to see if you should take supplements to meet your nutritional needs. Kelp, bone meal, and fish liver oil are paleo-friendly supplements that address the nutritional needs of people on a paleo diet.

References

  1. ^ a b c d Víctor de la O, et al. Scoping review of Paleolithic dietary patterns: a definition proposal. Nutr Res Rev. (2021)
  2. ^ a b c d Ehrika Vanessa Almeida de Menezes, et al. Influence of Paleolithic diet on anthropometric markers in chronic diseases: systematic review and meta-analysis. Nutr J. (2019)
  3. ^ a b c d e f g h i j Barbara Frączek, et al. Paleolithic Diet-Effect on the Health Status and Performance of Athletes?. Nutrients. (2021)
  4. ^ a b c d e f g h i j k l Ehsan Ghaedi, et al. Effects of a Paleolithic Diet on Cardiovascular Disease Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Adv Nutr. (2019)
  5. ^ a b c d e f g h i Mohammad Hassan Sohouli, et al. The effect of paleolithic diet on glucose metabolism and lipid profile among patients with metabolic disorders: a systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr. (2021)
  6. ^ a b c Małgorzata Jamka, et al. The Effect of the Paleolithic Diet vs. Healthy Diets on Glucose and Insulin Homeostasis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Clin Med. (2020)
  7. ^ a b c d e f g h i Eric W Manheimer, et al. Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis. Am J Clin Nutr. (2015)
  8. ^ a b c d e f g h i j Mellberg C, et al. Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial. Eur J Clin Nutr. (2014)
  9. ^ a b c Abdullah M Al Alawi, Asma Al Flaiti, Henrik Falhammar. Lactation Ketoacidosis: A Systematic Review of Case Reports. Medicina (Kaunas). (2020)
  10. ^ a b Shalini T Reddy, et al. Effect of low-carbohydrate high-protein diets on acid-base balance, stone-forming propensity, and calcium metabolism. Am J Kidney Dis. (2002)
  11. ^ a b Mary E Van Elswyk, Charli A Weatherford, Shalene H McNeill. A Systematic Review of Renal Health in Healthy Individuals Associated with Protein Intake above the US Recommended Daily Allowance in Randomized Controlled Trials and Observational Studies. Adv Nutr. (2018)
  12. ^ a b c d S Manousou, et al. A Paleolithic-type diet results in iodine deficiency: a 2-year randomized trial in postmenopausal obese women. Eur J Clin Nutr. (2018)
  13. ^ a b c d e f g h i j k l m Angela Genoni, et al. Cardiovascular, Metabolic Effects and Dietary Composition of Ad-Libitum Paleolithic vs. Australian Guide to Healthy Eating Diets: A 4-Week Randomised Trial. Nutrients. (2016)
  14. ^ a b c M Osterdahl, et al. Effects of a short-term intervention with a paleolithic diet in healthy volunteers. Eur J Clin Nutr. (2008)
  15. ^ a b c Karlsen MC, et al. Part 2: Theoretical Intakes of Modern-Day Paleo Diets: Comparison With Dietary Reference Intakes and MyPlate Meal Plans. Nutr Today. (2021)
  16. ^ a b Bligh HF, et al. Plant-rich mixed meals based on Palaeolithic diet principles have a dramatic impact on incretin, peptide YY and satiety response, but show little effect on glucose and insulin homeostasis: an acute-effects randomised study. Br J Nutr. (2015)
  17. ^ a b Tommy Jönsson, et al. A paleolithic diet is more satiating per calorie than a mediterranean-like diet in individuals with ischemic heart disease. Nutr Metab (Lond). (2010)
  18. ^ a b K S Culling, et al. Effects of short-term low- and high-carbohydrate diets on postprandial metabolism in non-diabetic and diabetic subjects. Nutr Metab Cardiovasc Dis. (2009)
  19. ^ a b Joshua Z Goldenberg, et al. Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data. BMJ. (2021)
  20. ^ a b Ojo O, et al. The Effect of Dietary Glycaemic Index on Glycaemia in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. (2018)
  21. ^ a b c d e f Toth N, Schick K. Overview of Paleolithic Archaeology. Handbook of Paleoanthropology. (2014)
  22. ^ a b c d e Klein RG. The human career: human biological and cultural origins. The University of Chicago Press. (2009)
  23. ^ a b S B Eaton, M Konner. Paleolithic nutrition. A consideration of its nature and current implications. N Engl J Med. (1985)
  24. ^ a b c d e f g h Amanda G Henry, Alison S Brooks, Dolores R Piperno. Plant foods and the dietary ecology of Neanderthals and early modern humans. J Hum Evol. (2014)
  25. ^ a b c Ainara Sistiaga, et al. The Neanderthal meal: a new perspective using faecal biomarkers. PLoS One. (2014)
  26. ^ a b c d H Pontzer, B M Wood, D A Raichlen. Hunter-gatherers as models in public health. Obes Rev. (2018)
  27. ^ a b c d e f Gauree G Konijeti, et al. Efficacy of the Autoimmune Protocol Diet for Inflammatory Bowel Disease. Inflamm Bowel Dis. (2017)
  28. ^ a b Robert D Abbott, Adam Sadowski, Angela G Alt. Efficacy of the Autoimmune Protocol Diet as Part of a Multi-disciplinary, Supported Lifestyle Intervention for Hashimoto's Thyroiditis. Cureus. (2019)
  29. ^ Anita Chandrasekaran, et al. An Autoimmune Protocol Diet Improves Patient-Reported Quality of Life in Inflammatory Bowel Disease. Crohns Colitis 360. (2019)
  30. ^ a b c d Kelly Fellows Maxwell, et al. Lipid profile is associated with decreased fatigue in individuals with progressive multiple sclerosis following a diet-based intervention: Results from a pilot study. PLoS One. (2019)
  31. ^ a b c Anna Revedin, et al. Thirty thousand-year-old evidence of plant food processing. Proc Natl Acad Sci U S A. (2010)
  32. ^ a b Price TD. The European Mesolithic. Am Antiq. (1983)
  33. ^ a b Otte M. The Paleolithic-Mesolithic Transition. Sourcebook of Paleolithic Transitions. (2009)
  34. ^ a b Maïté Rivollat, et al. Ancient genome-wide DNA from France highlights the complexity of interactions between Mesolithic hunter-gatherers and Neolithic farmers. Sci Adv. (2020)
  35. ^ a b Pontus Skoglund, et al. Origins and genetic legacy of Neolithic farmers and hunter-gatherers in Europe. Science. (2012)
  36. ^ a b c Kristine A Whalen, et al. Paleolithic and Mediterranean Diet Pattern Scores Are Inversely Associated with All-Cause and Cause-Specific Mortality in Adults. J Nutr. (2017)
  37. ^ Suzanna Maria Zick, Detrick Snyder, Donald I Abrams. Pros and Cons of Dietary Strategies Popular Among Cancer Patients. Oncology (Williston Park). (2018)
  38. ^ Jönsson T, et al. Subjective satiety and other experiences of a Paleolithic diet compared to a diabetes diet in patients with type 2 diabetes. Nutr J. (2013)
  39. ^ Kristine A Whalen, et al. Paleolithic and Mediterranean Diet Pattern Scores Are Inversely Associated with Biomarkers of Inflammation and Oxidative Balance in Adults. J Nutr. (2016)
  40. ^ a b Kristine A Whalen, et al. Paleolithic and Mediterranean diet pattern scores and risk of incident, sporadic colorectal adenomas. Am J Epidemiol. (2014)
  41. ^ a b Amanda K Irish, et al. Randomized control trial evaluation of a modified Paleolithic dietary intervention in the treatment of relapsing-remitting multiple sclerosis: a pilot study. Degener Neurol Neuromuscul Dis. (2017)
  42. ^ a b Terry L Wahls, et al. Impact of the Swank and Wahls elimination dietary interventions on fatigue and quality of life in relapsing-remitting multiple sclerosis: The WAVES randomized parallel-arm clinical trial. Mult Scler J Exp Transl Clin. (2021)
  43. ^ a b S Lindeberg, et al. A Palaeolithic Diet Improves Glucose Tolerance More Than a Mediterranean-like Diet in Individuals With Ischaemic Heart Disease. Diabetologia. (2007)
  44. ^ Li Xu, et al. Comparisons of body-composition prediction accuracy: a study of 2 bioelectric impedance consumer devices in healthy Chinese persons using DXA and MRI as criteria methods. J Clin Densitom. (Oct-Dec)
  45. ^ a b Jeannette M Beasley, et al. Associations between macronutrient intake and self-reported appetite and fasting levels of appetite hormones: results from the Optimal Macronutrient Intake Trial to Prevent Heart Disease. Am J Epidemiol. (2009)
  46. ^ . Obesity: preventing and managing the global epidemic. Report of a WHO consultation. World Health Organ Tech Rep Ser. (2000)
  47. ^ Courtney K Pickworth, et al. Randomized controlled trials investigating the relationship between dietary pattern and high-sensitivity C-reactive protein: a systematic review. Nutr Rev. (2019)
  48. ^ Lean ME, et al. Primary care-led weight management for remission of type 2 diabetes (DiRECT): an open-label, cluster-randomised trial. Lancet. (2018)
  49. ^ Christopher D Gardner, et al. Weight loss on low-fat vs. low-carbohydrate diets by insulin resistance status among overweight adults and adults with obesity: A randomized pilot trial. Obesity (Silver Spring). (2016)
  50. ^ Sydne J. Newberry, et al. Sodium and Potassium Intake: Effects on Chronic Disease Outcomes and Risks Internet.
  51. ^ Trexler E. Paleolithic Diet is Associated With Unfavorable Changes to Blood Lipids in Healthy Subjects. The Ohio State University. (2013)
  52. ^ Rebecca K Kelly, et al. Associations Between Macronutrients From Different Dietary Sources and Serum Lipids in 24 639 UK Biobank Study Participants. Arterioscler Thromb Vasc Biol. (2021)
  53. ^ C Vidon, et al. Effects of isoenergetic high-carbohydrate compared with high-fat diets on human cholesterol synthesis and expression of key regulatory genes of cholesterol metabolism. Am J Clin Nutr. (2001)
  54. ^ Cassandra E Forsythe, et al. Limited effect of dietary saturated fat on plasma saturated fat in the context of a low carbohydrate diet. Lipids. (2010)
  55. ^ Brittanie M Volk, et al. Effects of step-wise increases in dietary carbohydrate on circulating saturated Fatty acids and palmitoleic Acid in adults with metabolic syndrome. PLoS One. (2014)
  56. ^ Jennifer E Lee, et al. A Modified MCT-Based Ketogenic Diet Increases Plasma β-Hydroxybutyrate but Has Less Effect on Fatigue and Quality of Life in People with Multiple Sclerosis Compared to a Modified Paleolithic Diet: A Waitlist-Controlled, Randomized Pilot Study. J Am Coll Nutr. (2021)
  57. ^ Roess B. Thesis: Evolutionary Eating: A Critical Evaluation of the Paleo Diet. DePauw University. (2014)
  58. ^ S B Eaton, S B Eaton 3rd, M J Konner. Paleolithic nutrition revisited: a twelve-year retrospective on its nature and implications. Eur J Clin Nutr. (1997)
  59. ^ John Hawks, et al. Recent acceleration of human adaptive evolution. Proc Natl Acad Sci U S A. (2007)
  60. ^ a b c Todd Bersaglieri, et al. Genetic signatures of strong recent positive selection at the lactase gene. Am J Hum Genet. (2004)
  61. ^ a b c Sarah A Tishkoff, et al. Convergent adaptation of human lactase persistence in Africa and Europe. Nat Genet. (2007)
  62. ^ L Cordain, et al. Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets. Am J Clin Nutr. (2000)
  63. ^ Charlton S, et al. New insights into Neolithic milk consumption through proteomic analysis of dental calculus.. Archaeol Anthropol Sci. (2019)
  64. ^ Davis DR, Epp MD, Riordan HD. Changes in USDA food composition data for 43 garden crops, 1950 to 1999. J Am Coll Nutr. (2004)
  65. ^ Boers I, et al. Favourable effects of consuming a Palaeolithic-type diet on characteristics of the metabolic syndrome: a randomized controlled pilot-study. Lipids Health Dis. (2014)
  66. ^ a b Anthony Cioci, Chad Rudnick, Levonti Ohanisian. Accidental ketosis-induced polyuria in a toddler: a case report. BMC Pediatr. (2019)
  67. ^ Mackenzie Hartman, Bruce Fuller, Michael R Heaphy. Prurigo pigmentosa induced by ketosis: resolution through dietary modification. Cutis. (2019)
  68. ^ An Pan, et al. Red meat consumption and mortality: results from 2 prospective cohort studies. Arch Intern Med. (2012)
  69. ^ a b G C Curhan, et al. Comparison of dietary calcium with supplemental calcium and other nutrients as factors affecting the risk for kidney stones in women. Ann Intern Med. (1997)
  70. ^ a b Kossoff EH, et al. Optimal clinical management of children receiving dietary therapies for epilepsy: Updated recommendations of the International Ketogenic Diet Study Group. Epilepsia Open. (2018)
  71. ^ G C Curhan, et al. A prospective study of dietary calcium and other nutrients and the risk of symptomatic kidney stones. N Engl J Med. (1993)
  72. ^ Gary C Curhan, et al. Dietary factors and the risk of incident kidney stones in younger women: Nurses' Health Study II. Arch Intern Med. (2004)
  73. ^ Julia J Scialla, et al. Higher net acid excretion is associated with a lower risk of kidney disease progression in patients with diabetes. Kidney Int. (2017)
  74. ^ a b L A Frassetto, et al. Established dietary estimates of net acid production do not predict measured net acid excretion in patients with Type 2 diabetes on Paleolithic-Hunter-Gatherer-type diets. Eur J Clin Nutr. (2013)
  75. ^ a b Andreas F H Pfeiffer, et al. The Effects of Different Quantities and Qualities of Protein Intake in People with Diabetes Mellitus. Nutrients. (2020)
  76. ^ L Robertson, N Waugh, A Robertson. Protein restriction for diabetic renal disease. Cochrane Database Syst Rev. (2007)
  77. ^ Sevda Alvirdizadeh, et al. A prospective study on total protein, plant protein and animal protein in relation to the risk of incident chronic kidney disease. BMC Nephrol. (2020)
  78. ^ Parvin Mirmiran, et al. A Prospective Study of Dietary Meat Intake and Risk of Incident Chronic Kidney Disease. J Ren Nutr. (2020)
  79. ^ Diamond E, Tibaldi J. A Case Of Ketoacidosis In A Breastfeeding Patient On The Paleo Diet. Endocr Pract. (2016)
  80. ^ Sarah Gleeson, Eoin Mulroy, David E Clarke. Lactation Ketoacidosis: An Unusual Entity and a Review of the Literature. Perm J. (Spring)
  81. ^ Janet M Roseland, et al. Large Variability of Iodine Content in Retail Cow's Milk in the U.S. Nutrients. (2020)
  82. ^ Liu X, Baylin A, Levy PD. Vitamin D deficiency and insufficiency among US adults: prevalence, predictors and clinical implications. Br J Nutr. (2018)
  83. Jonas Andersson, et al. Left ventricular remodelling changes without concomitant loss of myocardial fat after long-term dietary intervention. Int J Cardiol. (2016)
  84. Ehsan Ghaedi, et al. Effects of a Paleolithic Diet on Cardiovascular Disease Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Adv Nutr. (2019)